fix(core): add ephemeral key to payment_create response when customer_id is mentioned (#1133)

crates/api_models/src/ephemeral_key.rs

@@ -0,0 +1,14 @@
+use serde;
+use utoipa::ToSchema;
+
+#[derive(Debug, serde::Serialize, serde::Deserialize, Clone, Eq, PartialEq, ToSchema)]
+pub struct EphemeralKeyCreateResponse {
+    /// customer_id to which this ephemeral key belongs to
+    pub customer_id: String,
+    /// time at which this ephemeral key was created
+    pub created_at: i64,
+    /// time at which this ephemeral key would expire
+    pub expires: i64,
+    /// ephemeral key
+    pub secret: String,
+}